1. Field of the Invention
The invention relates to a connection system, and in particular to a plug-in connection system for the transmission of data and power supply signals between a sensor means and a base unit in a measuring and transmission system. The term “connection system” as used in the present invention encompasses all possible coupling mechanisms which can be mechanically and electrically connected and isolated, plug connectors comprising a plug and socket element obviously being the most conventional examples of connectors of this type in electrical engineering.
2. Background Art
The contactless transmission of switch signals and AC voltages in telecommunications and data transmission systems is known from DE 195 40 854 A1, for example, in the form of an electromagnetic multiple coupler. The non-contact and passive transmission means of the multiple coupler used in this case supersede plug-in connections and allow electrical isolation of the electrical signals between, for example, a telecommunications and data transmission engineering main device and an external operator device such as is to be used, for example, in fields of application in which there is a risk of explosions such as fuel depots, oil conveying plants and oil refining plants.
DE 100 55 090 A1 discloses a plug-in connection system for connecting a transmission line to a sensor, which system also operates in a contactless manner and is provided with plug-internal electronics. The signals are transmitted inductively, the transmitted signal comprising a supply voltage signal and measurement signal in superimposed form.
The closest prior art is represented by DE 197 19 730 C1 which also relates to a plug-in connection system for the contactless transmission of data and power supply signals between a sensor means and a base unit in a measuring and transmission system. In this case, a sensor means, for example for a temperature probe, is coupled to a sensor-side plug-in connection element. The sensor means has a certain “intelligence”, as it has an A-D converter for the measurement signal of the thermocouple representing the measuring sensor and a microprocessor-assisted control and memory unit connected downstream thereof. In the sensor-side plug-in connection element, which is coupled to the sensor means, there is provided a data modulator/demodulator unit in combination with a power signal receiver, which unit is connected to a first coupling partner element of an inductive coupling for the contactless transmission of data and power supply signals. The second coupling partner element of the inductive coupling path is located in the base-side plug-in connection element which is linked, for the purposes of the supply of data and power, to the corresponding lines of a bus system. In this base-side plug-in connection element there is provided, again in combination, a data modulator/demodulator unit with a power signal transmitter, which unit powers the sensor system via the primary current supply originating from the bus system.
With regard to the invention, it should be noted that measuring and transmission systems of this type are often used in a harsh industrial environment such as, for example, in large-scale chemical processing plant. The measuring points are in such cases frequently far removed from the central control room. This gives rise to the problem that there is no direct possibility for the process operators to intervene on site at a measuring point on detection of an error state or a non-uniformity. Examples of such intervention include a calibration process on an electrochemical measuring sensor such as a pH probe.